It is a recognized practice to apply serving line to an archery bowstring. The center serving on the bowstring is intended to protect the bowstring in the area that it is applied from premature wear and abrasion due to the nocking and losing of the arrow.
Typically, a bowstring is assembled from multiple strands and displayed in position for applying serving line to the nock and loop end areas. Such a procedure is described in “Making A Bow String” Archer's Digest, 5th Edition, 1991, DBI Books. The procedure is time consuming, inefficient and inaccurate.
Bowstrings are generally made using one of two basic methods. One method consists of laying out multiple strands of a given length of a bowstring material and then dividing that material at the ends into two or more equal bundles and twisting or braiding these bundles into one single string or rope-like structure. The rope-like structure is then brought back on itself and is braided or twisted back into the original material to form an end loop.
A second method may be referred to in the art as an endless string. Using this method, a continuous strand of bowstring material is wrapped around two posts spaced apart at a distance which is approximately equal to that desired for the final bowstring length. The string is wrapped around the two posts until the desired number of strands is reached. The starting and ending point of the string is then tied together forming a splice. A separate piece of bowstring material is then typically wrapped or served over the area of the splice and end loops are formed by folding the served area back on itself and continuing to serve or wrap over the two sides of the string resulting in one multi-stranded bowstring with a loop at each end. The bowstrings thus made are usually held at one end while the other end is rotated to add twists to the main body of the string to bring the overall string length to a desired dimension that will result in the proper functioning of the bow on which the string is to be used. A bowstring so constructed is functional and can be used to launch arrows but unless one also wraps or serves the central portion of the string that comes in contact with the arrow the string will have a much shorter useful life expectancy than desired. Therefore it is desirable to also serve or wrap the bowstring in the area that comes in contact with the arrow and the means of losing the arrow. In almost all cases the bowstrings are served or wrapped in this area and it is referred to as the center serving. The center serving's purpose is to protect the central area of the bowstring from the wear that results from the attachment of the arrow and the means used to loose the arrow at launch.
FIGS. 1–4 illustrate a prior art center serving wherein a center serving is applied over a multiple strand bowstring body. A serving tool is typically employed for this purpose. A serving tool is described, for example, in U.S. Pat. No. 5,538,197, the entire content of which is incorporated by reference herein. To begin the wrapping process, approximately one foot of serving material 8 is pulled from the serving tool (not shown). The end 10 of the serving material 8 is held while the opposite end 12 of the serving material 8 which is attached to the serving tool (not shown) is wrapped around bowstring 20 twice as represented at 14 in FIG. 1. The loose end 10 of the serving is then laid back over the bowstring 20 as shown in FIG. 2.
In FIG. 3, end 12 attached to serving tool is then wrapped over the laid back end 10 in a continuous spiral fashion represented at 16 thereby encapsulating the bundled bowstring 20. Generally one wants to apply this serving as tight as possible with the idea that it will remain in position when finished. To finish off the central serving one can lay a loop 22 of serving material parallel to the bowstring with the loop 22 pointing in the direction of the end of the serving and extending beyond where the serving is to end as shown in FIG. 4. The serving material is then wrapped over loop 22 as well as shown at reference numeral 18 in FIG. 4. When the desired length of serving is obtained, end 12 of serving material is fed back through the loop 22 and with end 12 held tightly, loop ends 31, 32 are pulled tight resulting in the loop 22 to be drawn under the serving material. End 12 of serving material exits from serving at 19, and is pulled as tightly as possible and any excess material is removed.
The above methods required that the serving material be applied very tightly so that it will maintain its position during use. Some manufacturers have taken extra precautions to limit serving movement during use by applying the serving over a bowstring which is treated in the serving area with an adhesive or have applied materials over the serving in an attempt to hold the serving in position and to keep it from separating. These additional steps both add to the cost of manufacturing and increase the amount of clean-up time because of adhesive residue.
Over the useful life of the bowstring it is often necessary to add twists to the bowstring to compensate for the natural elongation of the bowstring material. The additional twists added to the bowstring can decrease the diameter of the bowstring resulting in loosening of the center serving.
Thus, while it has long been the practice to serve or wrap the bowstring in this central area it has also been a problem to keep that center serving tight and properly located in the central section of the bowstring.
The present invention provides an improved method of wrapping the central portion of the bowstring such that it is tight and remains properly positioned over time even if additional twists are added to the bowstring.